Silicon and ferrosilicon are produced in the form of ingots and are subjected to a crushing operation so that they are available to users in smaller size. During the crushing operation a very fine powder of silicon or ferrosilicon is formed and recovered from the filtering system. Through recent environmental regulations the amounts of silicon and ferrosilicon dusts has risen continuously thus creating a disposal problem for the manufacturers of silicon and ferrosilicon.
Attempts to find a use for such silicon and ferrosilicon powders have had little success because it must be appreciated that any agglomeration process must insure that the purity of the silicon or ferrosilicon is substantially retained. Accordingly most processes developed in the prior art have produced a product which is not equivalent in purity to the original product so that such agglomerated product can not be used instead of the pure product itself.
U.S. Pat. No. 4,128,417, Dec. 5, 1979 describes a process for the preparation of SiC and/or FeSi-containing fine materials to form metallurgically adjustable silicon bearers by binding the SiC and/or SiFe fines with a hydraulic binding agent such as cement or lime. This method produces a product containing 8-10% calcium oxide or 5,6 to 7% of calcium which amount renders it unsuitable to be used as pure silicon or ferrosilicon.
It is an object of the present invention to provide a metallurgical grade compacted unit of fine powdered silicon or ferrosilicon where the amount of impurities originally present have not been increased to a point where the product still retains the chemical qualities of the original silicon or ferrosilicon.